code: def forward(ctx, x):
      return x
  
file_path: glide-text2im/glide_text2im/clip/utils.py
imports: import math
  from typing import Callable, Optional
  import attr
  import torch
  import torch.nn
  import torch.nn.functional
label_desc: Use image node_id 1 for calling the ZeroKeyBiasGrad obj's underlying member method code with example usage: obj.forward(ctx, x) and returns: x